Carsberg, who has worked at the council since 1984, plans to undertake some consultancy work.
He said, "I am planning to work as a private consultant in the field of e-government and do some work in event management."
The move, which Carsberg describes as amicable, follows Braintree's recent decision to outsource its IT operation to services supplier ITNet.
Carsberg said, "It suited me to diversify and take up some new challenges."
In addition to spending more time with his grandchildren, Carsberg now hopes to devote more energy to his role as a qualified horticultural judge.
His stint as president of Socitm, which represents IT managers in local government, will also come to an end at the society's annual general meeting and spring seminar in Bolton next week.
"I may be accepting more speaking engagements in the next few months," he said.
Carsberg, who took over as Socitm president from Martin Ferguson in April 2001, quickly became an outspoken critic of last year's controversial Microsoft software licensing changes.
The society has since played a major part in negotiating the public-sector-wide software licensing deal that was announced between the Office of Government Commerce and Microsoft, IBM and Sun Microsystems earlier this year.
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